KeyValueStoreClient

An abstract class for key-value store (KVS) storage clients.

Key-value stores clients provide an interface for accessing and manipulating KVS storage. They handle operations like getting, setting, deleting KVS values across different storage backends.

Storage clients are specific to the type of storage they manage (Dataset, KeyValueStore, RequestQueue), and can operate with various storage systems including memory, file system, databases, and cloud storage solutions.

This abstract class defines the interface that all specific KVS clients must implement.

Hierarchy

• KeyValueStoreClient
  • FileSystemKeyValueStoreClient
  • MemoryKeyValueStoreClient
  • RedisKeyValueStoreClient
  • SqlKeyValueStoreClient

Index

Methods

• delete_value
• drop
• get_metadata
• get_public_url
• get_value
• iterate_entries
• iterate_keys
• purge
• record_exists
• set_value

Methods

delete_value

• async delete_value(*, key): None

• Overrides KeyValueStoreClient.delete_value

  Delete a value from the key-value store by its key.

  The backend method for the KeyValueStore.delete_value call.

  ---

  Parameters

  • keyword-onlykey: str

  Returns None

drop

• async drop(): None

• Overrides KeyValueStoreClient.drop

  Drop the whole key-value store and remove all its values.

  The backend method for the KeyValueStore.drop call.

  ---

  Returns None

get_metadata

• async get_metadata(): KeyValueStoreMetadata

• Overrides KeyValueStoreClient.get_metadata

  Get the metadata of the key-value store.

  ---

  Returns KeyValueStoreMetadata

get_public_url

• async get_public_url(*, key): str

• Overrides KeyValueStoreClient.get_public_url

  Get the public URL for the given key.

  The backend method for the KeyValueStore.get_public_url call.

  ---

  Parameters

  • keyword-onlykey: str

  Returns str

get_value

• async get_value(*, key): KeyValueStoreRecord | None

• Overrides KeyValueStoreClient.get_value

  Retrieve the given record from the key-value store.

  The backend method for the KeyValueStore.get_value call.

  ---

  Parameters

  • keyword-onlykey: str

  Returns KeyValueStoreRecord | None

iterate_entries

• async iterate_entries(*, exclusive_start_key, limit): AsyncIterator[KeyValueStoreRecord]

• Iterate over all the existing records in the key-value store, including their values.

  The backend method for the KeyValueStore.iterate_entries and KeyValueStore.iterate_values calls.

  The default implementation lists the keys with iterate_keys and reads each value separately with get_value as the iteration advances, so only a single value is held in memory at a time. Whether a record deleted while the iteration is in progress is yielded depends on the implementation. Backends that can read the keys together with their values more efficiently should override this method; such an implementation must still keep the memory usage bounded, e.g. by streaming or by batching on the known record sizes.

  ---

  Parameters

  • optionalkeyword-onlyexclusive_start_key: str | None = None

  • optionalkeyword-onlylimit: int | None = None

  Returns AsyncIterator[KeyValueStoreRecord]

iterate_keys

• async iterate_keys(*, exclusive_start_key, limit): AsyncIterator[KeyValueStoreRecordMetadata]

• Overrides KeyValueStoreClient.iterate_keys

  Iterate over all the existing keys in the key-value store.

  The backend method for the KeyValueStore.iterate_keys call.

  ---

  Parameters

  • optionalkeyword-onlyexclusive_start_key: str | None = None

  • optionalkeyword-onlylimit: int | None = None

  Returns AsyncIterator[KeyValueStoreRecordMetadata]

purge

• async purge(): None

• Overrides KeyValueStoreClient.purge

  Purge all items from the key-value store.

  The backend method for the KeyValueStore.purge call.

  ---

  Returns None

record_exists

• async record_exists(*, key): bool

• Overrides KeyValueStoreClient.record_exists

  Check if a record with the given key exists in the key-value store.

  The backend method for the KeyValueStore.record_exists call.

  ---

  Parameters

  • keyword-onlykey: str

    The key to check for existence.

  Returns bool

  True if a record with the given key exists, False otherwise.

set_value

• async set_value(*, key, value, content_type): None

• Overrides KeyValueStoreClient.set_value

  Set a value in the key-value store by its key.

  The backend method for the KeyValueStore.set_value call.

  ---

  Parameters

  • keyword-onlykey: str

  • keyword-onlyvalue: Any

  • optionalkeyword-onlycontent_type: str | None = None

  Returns None